Rabbi Yechiel Yaakov Weinberg (1884-1966) was a noted Orthodox rabbi, posek ("decisor" of Jewish law) and rosh yeshiva. He is best known as author of the work of responsa Seridei Eish.
Rabbi Weinberg was considered a genius in his time - with mastery over both Torah and secular subjects. An insightful and introspective individual, his varying interests in Talmud, musar, Hebrew literature, Russian language, and general academia make him one of the best representatives of the tumultuous intellectual trends present in his period.
Yechiel Yaakov Weinberg was born in Poland. He studied at the yeshivas of Mir and Slabodka. In the latter, "he combined within himself Lithuanian profound understanding of Halacha with the Slabodka musar expounded by the illustrious Alter, Rabbi Nosson Tzvi Finkel."
In 1906 he married 16-year-old Esther Levine, daughter of the deceased Rabbi Yaakov Meir. Under pressure from teachers and residents of the city of Pilwishki (Pilviškiai) which contained scholars of note, considerably his senior, he accepted the posts of spiritual rabbi and crown rabbi positions, and served for seven years. At the outbreak of World War I, he went to Germany. There he studied at the University of Giessen. Although Polish-born and Lithuanian-trained, Rabbi Weinberg "developed an extremely beautiful German prose style which was matched only by his mastery of modern Hebrew." He taught at and eventually became rector (rosh yeshiva) of the Hildesheimer Rabbinical Seminary in Berlin. His students included Rabbis Menachem Mendel Schneerson,Eliezer Berkovits, Giuseppe (Yoseph) Laras and Josef Hirsch Dunner.